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A comparative analysis of functional traits in semi-natural grasslands under different grazing intensities
Full text linkArticleThe reduction of traditional management practices is a major threat for the conservation of permanent grasslands in many European marginal areas. The ecological importance of grasslands is acknowledged by the European Habitats Directive 92/43/EEC (1992) which includes many natural or semi-natural grassland types, and by the growing attention of society towards functions and services provided by these ecosystems. Nonetheless, the efficiency of conservation policies is questioned also for the lack of local-scale information on trends and state of grasslands hampers the definition of local-tailored schemes. The main objective of this work is to assess the potential of a set of functional traits in discriminating between different management intensities and their capacity to describe the dynamics occurring in semi-natural grasslands. The research was carried out in a hilly area of Tuscany (Italy) on four grassland sites characterized by similar environmental features (soil, climate, topography), and by different management practices for 10 or more years. The survey concerned collection and analysis of different functional traits related to foliar features, litter and botanical composition. The functional traits were able to differentiate the four sites under different management practices, but their effectiveness was different. Results support the possibility to perform a rapid appraisal of grassland successional stages based on leaf functional traits of dominant species and by the assessment of presence of a reduced number of species among those occurring in the community
Perceived benefits from reclaimed rural landscapes: Evidence from the lowlands of the Po River Delta, Italy
Full text linkThe attention towards residents' perceptions of ecosystem services for an efficient management of rural landscapes is gaining momentum. One noteworthy aspect is the identification of links between perceived supply and societal demand of ecosystem services, as they can disclose leverages to improve rural policies. The objectives of this study are: i) to assess residents' perceptions of ecosystem services attributed to typical landscape elements; and ii) to characterise the perception of different groups of residents. We present the results from a residents' survey based on a phone-questionnaire carried out in a reclaimed coastal area, where vulnerabilities such as anthropic impact legacies and natural hazards are exacerbated. The aim of the questionnaire concerns the collection of information regarding people perception of benefits attached to a set of rural landscape elements and demand for services. The results show that awareness of regulating functions, the presence of disservices and the link with local food production relate with residents' perception of benefits from landscapes. Furthermore, we note that local landscape and the meaning attributed to historical land reclamation initiatives has a lasting influence on the perception of ecosystem services and that of such perceptions are significant for the design of land use policies
Benefits for the local society attached to rural landscape: An analysis of residents' perception of ecosystem services
Full text linkEcosystem services are the benefits for society deriving from ecosystems. The perception of ecosystem services by local residents is relevant to understand the extent to which such services contribute to society and regional development. The objective of this study is to assess the perception of ecosystem services associated to rural landscape by local residents and to use them to respond to two main questions: Are residents able to attribute flows of services from specific landscape elements to the different socioeconomic sectors? Are such perceptions affected by the different landscape features of the area of residency (e.g. rural vs. urban dwellers)? The analysis is carried out using data from a survey (n=295) in a rural area located in North Italy (Po Delta lowlands, Province of Ferrara). The results show that the urban population has a rather generic and positive consideration of ecosystem services associated to rural landscape elements and that perception is largely related to their recreational experience. The rural population has a more complex understanding of services and is more prone to acknowledge disservices associated to specific elements and/or specific socio-economic sectors. Such differences are likely connected to a more direct experience and to the different spatial scales that affect the perception of ecosystem services. The results indicate that cultural services such as recreation and actions linked to the promotion of the territory are commonly acknowledged. On the other hand, initiatives to enhance the awareness of less visible services (e.g. regulation services) would be useful for improving the valorization of specific landscape elements
Leaf functional traits for the assessment of succession following management in semi-natural grasslands: A case study in the North Apennines, Italy
No full textQuestion: Do leaf functional traits describe variation in the intensity of management in semi-natural grasslands? Location: Mugello, North Apennines, Italy. Methods: In an ecologically homogeneous area, we identified four grassland management practices (three different stocking rates and abandonment for 10 or more years). We measured leaf functional traits (LFT) of three dominant grass species - leaf dry matter content (LDMC), specific leaf area (SLA) and leaf N concentration (LNC) - in two permanent sampling plots per treatment for two consecutive years. Statistical tests and multivariate analysis were employed to compare the traits and analyse their sensitivity in responding to the different management intensities. Results: The robustness of LDMC and SLA in grass species ranking was confirmed. Weighted LDMC and SLA were able to differentiate the most intensely managed site from the others. Conclusions: The results of the weighted LDMC and the weighted SLA encourage further studies aimed at the development of a LFT database for the most common grass species of Apennine semi-natural grasslands. This could be of great help in the development of indicators able to support the formulation of rational management plans for conservation and sustainable animal production. © 2012 International Association for Vegetation Science
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Environmental and management drivers of alpine grassland vegetation types
Full text linkCurrent vegetation of alpine grasslands has been shaped by the combination of natural ecological factors (such as climate, soil, topography) and human activities, mainly represented by animal grazing and agricultural practices. An assessment of these factors can explain the present composition of plant communities and help to evaluate the future development of rangeland vegetation. Nowadays, the analysis of the botanical composition of grasslands is of a major importance in order to propose appropriate management plans for the sustainable exploitation of pastoralresources and their future conservation. The main purpose of this work was to assess the relevance of ecological and management factors in alpine grasslands in an area located in eastern Italy, currently used for extensive grazing, and to describe the main factors that affect the characteristics of pasture types. To this aim, about 900 ha of alpine grasslands were surveyed in Val Visdende (northern Veneto, province of Belluno, Italy) by means of 189 linear transects. Some environmental variables (altitude, slope, aspect) and factors related to management (pastoral value, animal excreta, distance from night barns) were collected for each botanical transect. Landolt indicators were calculated in order to evaluate the ecological space occupied by each type. This assessment made it possible to identify the most relevant grassland communities (namely nutrient poor, shrub encroached, nutrient rich and humid pastures) occurring in the studied area, the effectiveness of ecological indicators to describe and to differentiate vegetation groups and the effect of animal management and ecological factors in the discrimination of grassland types
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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